Repellent apparatus and method

ABSTRACT

A method of repelling animals from an area which includes the step of causing at least one flexible tube to move, at least within part of the area, by means of a pressurised fluid.

BACKGROUND OF THE INVENTION

This invention relates to a method of and apparatus for repellinganimals from a given area.

The invention is described hereinafter with particular reference torepelling animals such as birds from an area such as an airport in anaircraft hanger or other building, on external surfaces eg. ledges orbalconies in a building, from agricultural areas eg. vineyards, orchardsetc, and from sports fields such as golf courses and the like. The scopeof the invention is not confined to these particular applications whichare given by way of examples only. Generally the principles of theinvention are applicable to repelling animals (birds or ground animals)from an area which is in the open or inside or on a building.

The presence of birds at an airport constitutes a significant safetyhazard to aircraft which are landing at, or taking off from, theairport. A typical airport extends over a substantial area and can havea large number of runways laid out in different directions over thearea. Vegetation, typically grass, is established or naturally grows onthe surfaces between runways. This vegetation can play host to a varietyof animals and, in particular, to birds which, with the passage of time,can establish themselves and form large colonies.

If an aircraft which is landing or taking off at a runway collides witha bird or a flock of birds, or draws one or more birds into its airintake to one of its engines, the consequences can be disastrous.

Much effort has been expended in attempts to repel birds from an airportand, more particularly, from ground which is adjacent runways. Diversetechniques exist including noise generators, scarecrows, ultrasonictransmitters, electrical devices which apply mild electric shocks,electrically operated scarecrows and the like. It has been found thatalthough these devices may, at least initially, be effective they areoften not effective against all bird species but, more importantly, withthe passage of time habituation lessens the effectiveness of thedevices. Habituation is the waning of responsiveness to a deterrentwhich occurs when birds learn that the deterrent, as a matter of fact,does not present danger.

Although it may be possible to control bird populations by killing thebirds this may be undesirable from an environmental point of view. Thisapproach can also lead to a public outcry.

A related problem presents itself in hangers and other lofty buildingsin or on which birds can seek sanctuary effectively protected by thesubstantial distance which exists between humans, on the ground, and theperches of the birds. Droppings from these birds can cause seriousdamage to equipment and machinery, mar a building and can constitute aserious health hazard.

SUMMARY OF INVENTION

The invention provides in the first instance a method of repellinganimals from an area which includes the step of causing at least onedevice to move, at least within part of the area, by means of apressurised fluid.

The device may be caused to move substantially randomly, or in apredetermined manner.

The time at which the device is caused to be moved may be varied,according to requirement.

The pressurised fluid may comprise any suitable pressurised fluid andfor example may comprise compressed air.

One or more substances may be entrained in the pressurised fluid. Thesubstance could for example be selected from the following: water, sand,mud and the like.

The invention is not limited in this regard. The device may be flexibleand may be caused to move with a whip action due to the pressurisedfluid which flows through the device.

The pressurised fluid may be allowed to escape from the device throughone or more nozzles which may be shaped to cause a reaction force whichhelps to cause movement of the device.

The device may be caused to rotate around an axis.

A plurality of the devices may be actuated so that they aresimultaneously caused to move, or so that they are caused to move insuccession in a predetermined sequence, or randomly.

The invention also provides apparatus for repelling animals from an areawhich includes a device with an inlet which is adapted to be connectedto a source of pressurised fluid and which is constructed so that it ismovable by application of the pressurised fluid to the inlet.

The pressurised fluid is preferably compressed air.

The device may include a tube. The tube may be elongate and flexible.The tube may include one or more outlet nozzles through whichpressurised fluid escapes from the tube. These nozzles may be orientedto assist in causing movement of the tube.

Alternatively, in the case in which the tube is flexible, the tube maybe caused to move, substantially in a random manner, by the flow ofcompressed air through the tube.

Means may be provided for entraining a substance into the flow ofpressurised fluid through the tube. The substance may be sand, water,mud or the like.

In one form of the invention the device is caused to rotate around afixed axis.

The device may be elevated, at least to a limited extent, uponapplication of the pressurised fluid to the inlet and it may be allowed,to settle, under gravity or other action, to an inoperative positionwhen the pressurised fluid is not applied to the inlet.

The invention also extends to a system which includes a network, aplurality of the devices which are connected to the network, a source ofpressurised fluid and a control unit, for applying the pressurisedfluid, via the network, to one or more of the devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is further described by way of examples with reference tothe accompanying drawings in which:

FIG. 1 is a schematic plan view of an airfield in which the method ofthe invention is used for repelling birds from areas adjacent runways atthe airfield;

FIGS. 2, 3 and 4 respectively illustrate different devices which areusable in the method of the invention; and

FIG. 5 illustrates a system for repelling animals in a diagrammaticform.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 of the accompanying drawings illustrates in plan an airfield 10which includes a plurality of runways 12. Only one runway is shown inthe drawing and it is to be understood that other runways at theairfield are treated in substantially the same way as what is describedhereinafter.

The runway 12 is normally formed from concrete or a similar hardwearingsurface. An aircraft 14 may traverse the runway in either direction.These aspects are known in the art and are not further described herein.

Ground 16 adjacent the runway 12 comprises bare earth over whichvegetation, not shown, is established. Typically this vegetationincludes one or more varieties of grass, as has been describedhereinbefore. The vegetation may play host to one more species of birdsor other animals and these animals could present a safety hazard to theaircraft 14.

An air distribution network is constructed from main pipelines 18 whichare buried in the ground, on each side of the runway 12, at a suitabledepth. At intervals along the length of each line 18 a riser tube 20 isconnected to the line. Each tube terminates in a housing 22 whichcontains a connector and a solenoid valve. A flexible tube 24 is fixedto the connector and extends in a random manner from the connector. Thetube 24 has a length which ensures that it cannot overlay a portion ofthe runway 12.

A compressed air source 26 is connected to the main line 18. Dependingon the situation the compressed air source may comprise a large pressurevessel or a dedicated air compressor with an optimal storage tank. Ifappropriate use can be made of both devices. An intention in this regardis that the compressed air source should work at a controlled pressureand supply sufficient compressed air to the line 18 to activate one ormore of the hoses 24 in a manner which is described hereinafter.

The compressed air source is under the control of a control unit 28. Thevarious solenoid valves at each riser tube 20 are connected by means oflines 30 to the control unit 28.

FIG. 2 illustrates one of the flexible tubes 24. The tube is coupled toa connector 32 which is fixed to the corresponding housing 22 in whichis installed a solenoid valve 34. The riser tube 20 extends from themain line 18 which, as noted, is buried in the ground at a desired depth36.

If compressed air, designated by means of an arrow 40, is applied to themain line 18, from the source 26, and the solenoid valve 34 is openedthen the compressed air flows through the flexible hose 24. Depending onthe pressure and the characteristics of the hose the flow of air,through the hose, can cause the hose to move with a whip action in asubstantially random manner. If the ground 16 adjacent the runway 12 isto be cleared of animals and, in particular, birds, then the compressedair 40 is applied to the various hoses 24 in a manner which isdetermined by a program in the control unit 28 which causes thecorresponding solenoid valves 34 to open and close as required. Thehoses can be caused to move in a fairly vigorous manner which is notpredictable and the sequence in which the hoses are activated can alsobe varied in a non-predictable manner. Birds in the vegetation adjacentthe runway are thereby repelled and the area adjacent the runway isfreed of bird life. The safety of the aircraft 14 is thereforeconsiderably enhanced.

The repelling apparatus of the invention can be operated at differentintervals, on an ongoing basis, or it can be operated before an aircrafttakes off from, or lands on, the runway 12. Some degree ofexperimentation may be required in order to ascertain the most effectiveway, under the circumstances, of making use of the invention.

FIG. 2 illustrates a vessel 42 with an outlet conduit 44 which isconnected to the line 18. The vessel may contain water, sand, mud 46 orany other appropriate substance. When air flows through the main line 18a portion of the substance in the vessel is entrained into the air flowand is distributed through an outlet end 48 of the flexible hose 24. Ifthe substance 46 is, for example, sand then the sand is ejected from theend 48 at high speed, depending on the velocity of the escaping air, andthis can add to the deterrent effect of the hose which is flexing to andfro.

FIG. 3 illustrates a variation which can be incorporated in theapparatus shown in FIG. 1. Inflatable scarecrows 50 are connected to theline 18 at regular intervals. The scarecrows can be inflated by thecompressed air and when this happens each scarecrow, which is initiallyin a collapsed state, is caused to move to an erect position in a shorttime. The sudden movement can assist in repelling birds from a givenarea. The inflation of each scarecrow is controlled by means of thecontrol unit 28 which is connected via a control line 30 to a solenoidvalve 34 which controls the flow of air from the line 18 to thescarecrow figure. If the inflation of the scarecrow is associated withthe actuation of a hose 24, by animals in the area, then air usage maybe reduced if the hose is not actuated every time the scarecrow isinflated.

FIG. 4 illustrates a further variation of the invention. Each housing 22is formed in the nature of a “pop-up” device 60 similar to a pop-upsprinkler used in an irrigation system. Thus the housing includes atubular body 62 which contains a swivel connector 64 which is mounted toa riser tube 20 in sliding fashion. When compressed air is applied tothe swivel connector the resulting force causes the swivel connector torise along the length of the tube 20 and the corresponding end of thehose 24 which is coupled to the connector is elevated. When the supplyof compressed air is disconnected from the swivel connector air escapesfrom the swivel connector which then settles under gravity action, intothe tubular casing 62. This arrangement has a number of benefits.Firstly it allows the tube 24 to be elevated when air is applied to it.The degree of elevation can be controlled so that the tube is liftedabove the grass which may be growing on the ground 16 adjacent therunway. Secondly when the device is not being used it settles into theground and thus does not present any obstruction to traffic over theground 16.

A further modification is shown in FIG. 4. The tube 24 which may behighly flexible or substantially rigid has one or more nozzles 66 at itsoutlet end 48. These nozzles are shaped so that air escaping from thenozzles exerts a reaction force on the tube 24 which causes it to rotateabout the swivel connector 64 as is indicated by means of a curved arrow68. The tube can be caused to rotate fairly rapidly and vigorously sothat birds adjacent the tube are repelled from the vicinity of the tube.

The period for which the tube 24 is caused to move, and the timeinterval between successive actuations of the tube, may be varied toachieve optional results.

It is to be understood that the apparatus of the invention is notintended to cause injury to birds but, instead, is designed to makeconditions adjacent the runway unacceptable to bird life. As the hosesmove vigorously it is possible, however, for the hoses to cause injuryto birds. This can be a positive factor though, for a learning processsets in. The birds associate the moving hoses with danger and aretherefore likely to fly away from the areas in which the hoses areinstalled and used.

FIG. 5 is a generalised representation of an animal repelling system 70according to the invention based on the preceding principles. The systemincludes a compressor or compressed air source 72 which is connected toa plurality of solenoid valves 74A, 74B, 74N by means of an airdistribution network 76 formed, for example, from plastic tubing. Eachsolenoid is used to control the supply of air from the network to arespective flexible plastic tube 78A, 78B, . . . . 78N.

A control unit 80, which may be a micro processor-based device such as aprogrammable logic controller, is used to control the actuation of thevarious solenoid valves. The control unit is connected to a power supply82 of any appropriate type and is connected to the solenoid valves via acable network 84 which may for example be a two or three wire network.

Each of the solenoids 74 includes a respective decoder 86A, 86B . . .86N, and a respective unique code is associated with each of thesolenoids.

The control unit is programmed to generate, at any time, one or more ofthe codes which are associated with the solenoids. The codes can begenerated in a controlled sequence so that, for example, the codesassociated with the solenoids 74A, 74B . . . 74N are generated in thatsequence. Alternatively the codes can be generated in a random orpseudo-random fashion. The latter course of action is preferable in thatit then becomes practically impossible, particularly for an animal, topredict which solenoid will be actuated at any time.

The codes which are generated by the control unit 80 are presentedsimultaneously via the cable network 84 to the decoders 86. If a code onthe cable network is validated by a respective decoder then the solenoidassociated with that decoder is actuated and the remaining solenoids arekept closed. Power from the supply 82 is transmitted over the network 84and is used to energise the selected solenoid.

As has been noted hereinbefore when a solenoid is opened air from thecompressed air source in the system is vented to atmosphere through therespective tube 78 and the release of energy in the compressed air,flowing through the tube, causes the tube to flex and move substantiallyrandomly through the air. This acts as a significant deterrent for, atthe same time, a fair amount of noise is generated as air escapes fromthe tube. Depending on the pressure the compressed air can cause therespective tube 78 to move violently and it is possible for the tube toinjure or kill a small animal. On the other hand by adjusting the airpressure the vigorous movement of the hose 78 can be attenuated, ifrequired.

A system 70 of the kind shown in FIG. 5 can be installed at anyappropriate location for example inside a building such as a hanger, onrafters of the building, outside a building on ledges or balconies orother locations at which birds are prone to congregate, on a golfcourse, particularly at the putting greens which should be protectedfrom large numbers of birds, and in agricultural installations such asat orchards, vineyards and the like.

1. A method of repelling animals from an area which includes the stepsof pressurising at least one flexible tube with compressed air and,while pressurizing the tube, allowing compressed air to escape from thetube through at least one nozzle to cause a reaction force which causesmovement of the tube within the area.
 2. A method according to claim 1wherein the tube is caused to move substantially randomly.
 3. A methodaccording to claim 1 wherein the tube is caused to move for a periodwhich is variable.
 4. A method according to claim 3 wherein a timeinterval between successive periods during which the tube is caused tomove, is variable.
 5. A method according to claim 1 wherein at least onesubstance is entrained in the compressed air.
 6. A method according toclaim 5 wherein the substance is selected from water, sand and mud. 7.Apparatus for repelling animals from an area which includes a source ofcompressed air, at least one flexible tube with an inlet which isconnected to the source of compressed air, and at least one outletnozzle through which compressed air escapes from the flexible tube whilethe tube is connected to the source of compressed air thereby to causemovement of the tube within the area.
 8. Apparatus according to claim 7wherein the tube is elongate and flexible.
 9. Apparatus according toclaim 7 wherein the at least one outlet nozzle is oriented to assist incausing movement of the flexible tube.
 10. Apparatus according to claim7 wherein the tube is caused to rotate around a fixed axis. 11.Apparatus according to claim 7 wherein the tube is elevated uponapplication of the compressed air to the inlet and is allowed to settleto an inoperative position when the compressed air is not applied to theinlet.
 12. A system for repelling animals from an area which includes acompressed air distribution network, apparatus according to claim 7,which includes a plurality of the flexible tubes, connected to thenetwork, and a control unit for applying the compressed air via thenetwork, in a controlled manner, to the flexible tubes.